Add basic Chrome interaction with the mash shelf.

ash/mus/sysui_application.h

Index: ash/mus/sysui_application.h
diff --git a/ash/mus/sysui_application.h b/ash/mus/sysui_application.h
index 552f21080ed96052c94526d67c8ad968c72a8075..1d42600d59409774bc17d00c7383702b8f15e661 100644
--- a/ash/mus/sysui_application.h
+++ b/ash/mus/sysui_application.h
@@ -8,6 +8,8 @@
 #include <memory>
 
 #include "base/macros.h"
+#include "mash/shelf/public/interfaces/shelf.mojom.h"
+#include "mojo/public/cpp/bindings/binding_set.h"
 #include "mojo/services/tracing/public/cpp/tracing_impl.h"
 #include "mojo/shell/public/cpp/shell_client.h"
 
@@ -16,7 +18,9 @@ namespace sysui {
 
 class AshInit;
 
-class SysUIApplication : public mojo::ShellClient {
+class SysUIApplication
+    : public mojo::ShellClient,
+      public mojo::InterfaceFactory<mash::shelf::mojom::ShelfController> {
  public:
   SysUIApplication();
   ~SysUIApplication() override;
@@ -28,9 +32,17 @@ class SysUIApplication : public mojo::ShellClient {
                   uint32_t id) override;
   bool AcceptConnection(mojo::Connection* connection) override;
 
+  // InterfaceFactory<mash::shelf::mojom::ShelfController>:
+  void Create(mojo::Connection* connection,
+              mojo::InterfaceRequest<mash::shelf::mojom::ShelfController>
+                  request) override;
+
   mojo::TracingImpl tracing_;
   std::unique_ptr<AshInit> ash_init_;
 
+  mojo::BindingSet<mash::shelf::mojom::ShelfController>
+      shelf_controller_bindings_;
+
   DISALLOW_COPY_AND_ASSIGN(SysUIApplication);
 };